Using Surface Electromyography to Analyze Masticatory Muscle Activation Across Postural Variations

Session Number

3

Advisor(s)

Dr. Ashwin Mohan, SYNAPSE Lab, IMSA

Location

A150

Discipline

Medical and Health Sciences

Start Date

15-4-2026 2:15 PM

End Date

15-4-2026 3:00 PM

Abstract

Posture and body position influence muscle mechanics, but their role in masticatory muscle balance during chewing has received little attention. The objective of this study was to identify whether natural head posture, forward head posture, or standing promotes the most balanced bilateral activation of the masticatory muscles. Using surface electromyography (sEMG), we measured electrical activity in the left and right masseter and temporalis muscles while participants performed standardized chewing tasks in each postural condition. Muscle activation data were normalized to maximum voluntary contraction, and bilateral muscle balance was quantified using signal processing in MATLAB, including filtering, rectification, and root mean square analysis. Understanding how posture influences masticatory muscle balance has important clinical implications for stroke rehabilitation. Many stroke survivors experience unilateral motor impairment, leading them to rely on the stronger side during chewing, which can cause muscle overuse and asymmetrical mechanical stress on the jaw. Findings from this study may inform posture-based interventions that provide a simple and noninvasive approach to encourage more symmetrical muscle recruitment during chewing, while supporting motor recovery and preventing overuse.

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Apr 15th, 2:15 PM Apr 15th, 3:00 PM

Using Surface Electromyography to Analyze Masticatory Muscle Activation Across Postural Variations

A150

Posture and body position influence muscle mechanics, but their role in masticatory muscle balance during chewing has received little attention. The objective of this study was to identify whether natural head posture, forward head posture, or standing promotes the most balanced bilateral activation of the masticatory muscles. Using surface electromyography (sEMG), we measured electrical activity in the left and right masseter and temporalis muscles while participants performed standardized chewing tasks in each postural condition. Muscle activation data were normalized to maximum voluntary contraction, and bilateral muscle balance was quantified using signal processing in MATLAB, including filtering, rectification, and root mean square analysis. Understanding how posture influences masticatory muscle balance has important clinical implications for stroke rehabilitation. Many stroke survivors experience unilateral motor impairment, leading them to rely on the stronger side during chewing, which can cause muscle overuse and asymmetrical mechanical stress on the jaw. Findings from this study may inform posture-based interventions that provide a simple and noninvasive approach to encourage more symmetrical muscle recruitment during chewing, while supporting motor recovery and preventing overuse.